This invention relates generally to asphalt concrete repair apparatus and more particularly to heating units utilized to soften areas of asphalt pavement.
The idea of heating existing asphalt pavement where it lies on the roadway in order to rejuvenate and make repairs is an old one and a good one. It eliminates lifting and trucking the old asphalt away as well as buying all new asphalt concrete to truck in and spread.
A variety of asphalt heating machines have been produced. They have employed direct flame, steam, microwaves, infrared radiation, etc. to convey heat into the road surface. The best machine for this application would quickly and safely get the heat in for the lowest cost.
It was the intent of the inventor to produce an inexpensive and manuverable infrared heating machine that could effectively heat asphalt roadways. Experiments with forcing combustible air and gas mixture through refractory blanket showed that the blanket could be used as an efficient radiant surface burner medium. Its flexibility and lightweight ideally suited it to use in such a machine. The weight was so decreased by its use instead of rigid refractory material that it was possible to handle over 60 square feet of heating surface manually, eliminating the cost and weight of hydraulics or winches. Complete mobility of the heater speeded repairs and allowed them to be done at any angle relative to the plane of the road.
The light weight of the device makes possible the folding trailer enclosure for the heater. Lifting at the hinged middle folds the machine in half into the trailering position which protects the burner medium during transport and eliminates the need for a separate trailer. A separate trailer would be in the way behind the towing vehicle which may be advantageously used to carry asphalt. The reduction of weight makes the heater more useable and decreases its cost.